At a Glance
- Tasks: Develop and maintain WebExtensions APIs for Firefox, ensuring user safety and performance.
- Company: Join Mozilla, a non-profit tech leader shaping the internet for over 25 years.
- Benefits: Enjoy competitive salary, health coverage, remote work, and generous professional development support.
- Other info: Diverse and inclusive workplace with excellent career growth opportunities.
- Why this job: Make a real impact on millions of users while working with cutting-edge technology.
- Qualifications: 4+ years in software development with strong JavaScript skills; bonus for Rust or C++ experience.
The predicted salary is between 66000 - 87000 £ per year.
Mozilla is hiring a remote candidate for Senior Software Engineer, WebExtensions. This is a full time position. Work location: UK.
The role typically involves technologies such as JavaScript, Redis, Rust, Java, software engineering, engineer.
Key Responsibilities- Implement and maintain WebExtensions APIs and Addon Management, balancing power, safety, and performance, as well as user interfaces in Firefox.
- Debug and fix issues affecting extensions in Firefox.
- Collaborate with product managers, QA, and the AMO engineering team to deliver features end-to-end.
- Contribute to Mozilla-owned extensions and system add-ons.
- Participate in open source workflows: code reviews, pull requests, and discussions in Bugzilla/GitHub.
- Support extension developers by helping diagnose issues and improving tooling/documentation.
Primary Skills: JavaScript, Redis, Rust, Java
Secondary Skills: software engineering, engineer, front end, architecture
Skills required for this role include JavaScript, Redis, Rust, and related tools for day-to-day development.
Job Details- Employment Type: Full Time
- Location: UK
- Salary: $83820 – $110490 USD
JavaScript, Redis, Rust, Java, software engineering, engineer, front end, architecture
About this team and role:The WebExtensions platform powers the add-ons ecosystem in Firefox, enabling millions of users to customize their browser while keeping safety and performance at the forefront. As a WebExtensions Engineer, you will help implement new extension capabilities, improve existing APIs, and ensure that extensions remain reliable across Firefox.
As a Software Engineer on the WebExtensions team, you’ll bring a passion for exploring complex systems and creating experiences that balance developer power with user trust. You’ll work deep in the Gecko platform to evolve extension capabilities, and you’ll build UI features in Firefox that make extensions clear and manageable for users. Along the way, you’ll collaborate with experts across Mozilla and help advance cross-browser compatibility and the path toward standardization. Your work will keep extensions safe, powerful, and reliable for developers and millions of Firefox users.
What you’ll do:4+ years of professional experience in software development.
Strong proficiency in JavaScript, DOM APIs, HTML, and CSS.
Familiarity with modern browser architecture and debugging tools.
Experience with API design and integration.
Ability to navigate and learn from large codebases.
Strong communication skills and experience collaborating in distributed teams.
Bonus points for:
- Experience with Firefox internals, C++ or Rust.
- Familiarity with Android or GeckoView development.
- Knowledge of web security principles.
- Contributions to open source projects, especially in browser or extension development.
- Generous performance-based bonus plans to all eligible employees - we share in our success as one team
- Rich medical, dental, and vision coverage
- Generous retirement contributions with 100% immediate vesting (regardless of whether you contribute)
- Quarterly all-company wellness days where everyone takes a pause together
- Country specific holidays plus a day off for your birthday
- One-time home office stipend
- Annual professional development budget
- Quarterly well-being stipend
- Considerable paid parental leave
- Employee referral bonus program
- Other benefits (life/AD&D, disability, EAP, etc. - varies by country)
Mozilla exists to build the Internet as a public resource accessible to all because we believe that open and free is better than closed and controlled. When you work at Mozilla, you give yourself a chance to make a difference in the lives of Web users everywhere. And you give us a chance to make a difference in your life every single day. Join us to work on the Web as the platform and help create more opportunity and innovation for everyone online.
Commitment to diversity, equity, inclusion, and belongingMozilla understands that valuing diverse creative practices and forms of knowledge are crucial to and enrich the company’s core mission. We encourage applications from everyone, including members of all equity-seeking communities, such as (but certainly not limited to) women, racialized and Indigenous persons, persons with disabilities, persons of all sexual orientations, gender identities, and expressions.
We will ensure that qualified individuals with disabilities are provided reasonable accommodations to participate in the job application or interview process, to perform essential job functions, and to receive other benefits and privileges of employment, as appropriate. Please contact us at hiringaccommodation@mozilla.com to request accommodation.
We are an equal opportunity employer. We do not discriminate on the basis of race (including hairstyle and texture), religion (including religious grooming and dress practices), gender, gender identity, gender expression, color, national origin, pregnancy, ancestry, domestic partner status, disability, sexual orientation, age, genetic predisposition, medical condition, marital status, citizenship status, military or veteran status, or any other basis covered by applicable laws. Mozilla will not tolerate discrimination or harassment based on any of these characteristics or any other unlawful behavior, conduct, or purpose.
Senior Software Engineer, WebExtensions employer: Far Coder
Mozilla is an exceptional employer that champions a culture of innovation and inclusivity, allowing employees to contribute to meaningful projects that shape the future of the internet. With generous benefits including performance-based bonuses, comprehensive health coverage, and a commitment to professional development, Mozilla fosters an environment where team members can thrive both personally and professionally. Working remotely from the UK, you'll join a diverse team dedicated to making the web a safer and more accessible place for everyone.
StudySmarter Expert Advice🤫
We think this is how you could land Senior Software Engineer, WebExtensions
✨Tip Number 1
Get your networking game on! Reach out to folks in the industry, especially those at Mozilla. A friendly chat can go a long way, and who knows, they might even put in a good word for you!
✨Tip Number 2
Show off your skills! If you've got a GitHub or portfolio showcasing your work with JavaScript, Rust, or any relevant tech, make sure to share it during interviews. It’s a great way to demonstrate your expertise.
✨Tip Number 3
Prepare for those technical interviews! Brush up on your coding skills and be ready to tackle some real-world problems. Practising common algorithms and system design questions can really help you shine.
✨Tip Number 4
Don’t forget to apply through our website! It’s the best way to ensure your application gets seen by the right people. Plus, mentioning 'FarCoder' shows you’ve done your homework and are genuinely interested.
We think you need these skills to ace Senior Software Engineer, WebExtensions
Some tips for your application 🫡
Show Your Passion:When you're writing your application, let your enthusiasm for software engineering and the WebExtensions platform shine through. We want to see that you’re genuinely excited about the role and how you can contribute to Mozilla's mission.
Tailor Your CV:Make sure your CV highlights your experience with JavaScript, Redis, Rust, and any other relevant technologies. We love seeing how your skills align with what we’re looking for, so don’t be shy about showcasing your best work!
Mention 'FarCoder':Don’t forget to include the word 'FarCoder' in your application! This shows us that you’ve read the job post thoroughly and are serious about joining our team. It’s a small detail that makes a big difference.
Apply Through Our Website:We encourage you to apply directly through our website. It’s the best way to ensure your application gets into the right hands. Plus, it gives you a chance to explore more about us and what we stand for!
How to prepare for a job interview at Far Coder
✨Know Your Tech Stack
Make sure you’re well-versed in JavaScript, Redis, Rust, and Java. Brush up on your knowledge of DOM APIs and modern browser architecture. Being able to discuss these technologies confidently will show that you’re ready to tackle the challenges of the role.
✨Showcase Your Problem-Solving Skills
Prepare to discuss specific examples where you've debugged issues or improved existing APIs. Think about how you’ve contributed to open-source projects or collaborated with teams to deliver features. This will demonstrate your hands-on experience and ability to work in a team.
✨Understand Mozilla's Mission
Familiarise yourself with Mozilla’s core mission to make the internet better for people. Be ready to discuss how your values align with theirs and how you can contribute to their goals, especially in enhancing user trust and safety in extensions.
✨Ask Thoughtful Questions
Prepare some insightful questions about the WebExtensions team and their current projects. This shows your genuine interest in the role and helps you understand how you can fit into their culture and contribute effectively.
